Introduction
The Japanese Army Air Force and the Japanese Navy Air Force each use a distinctive set of fuzes. Therefore, this section is divided into two main parts, Army and Navy.
Individual fuzes and gaines of each service are generally interchangeable for use in bombs of that service but are not interchangeable for use in ordnance of the other. Each group possesses certain definite identifying characteristics.
Army Fuzes
1. Arming vanes have holes for arming wires.
2. Safety forks are usually fitted over the vanes into holes in the top of the fuze body.
3. Most fuzes have the primer as an integral part of the fuze.
Navy Fuzes
1. Arming vanes do not have holes for arming wires.
2. Safety forks or safety pins are usually inserted into the fuze body from the side.
3. The fuze seldom has the primer as an integral part of the fuze.
Designation
At the beginning of the war little was known about the Japanese designations for their fuzes. The Allies developed a system of nomenclature consisting of three parts, (1) a capital letter, (2) a numeral, (3) a small parenthetical letter.
1. The capital letter denotes the basic type of fuze:
A - Nose impact fuze.
B - Tail impact fuze.
C - Long delay fuze (nose or tail).
D - Aerial burst fuze (nose or tail).
E - Protective fuze (nose or tail).
2. The numeral indicates the approximate order of recovery by the Allied forces of different basic designs of fuzes within the general classification of A, B, C, D, or E.
3. The small letter in parentheses indicates whether the fuze is the first, second, etc. example of a basic design. The difference between A-2(a) and A-2(b) is roughly equivalent to the difference between modifications of a certain mark of US Navy ordnance.
The Allied system of designations makes no distinction between Japanese Army and Japanese Navy fuzes.
Wherever possible, the Japanese designation and Allied designation appear in the title. If no Japanese designation is given it indicates that the Japanese had no separate designation for this fuze.
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